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Finding the Fourth Proportional to 640.17, 960.21 and 425.16

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Solution

The fourth proportional to 640.17, 960.21 and 425.16 is: 637.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.17 : 960.21 = 425.16 : x
  2. Step 2: Convert to fraction form
    640.17/960.21 = 425.16/x
  3. Step 3: Cross multiply
    640.17x = 960.21 × 425.16
  4. Step 4: Simplify right side
    640.17x = 408,242.88
  5. Step 5: Solve for x
    x = 408,242.88/640.17
  6. Step 6: Final answer
    x = 637.71

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.